We have carried out high level gas phase quantum chemical calculations of the relative energetics of the alanine tetrapeptide, using the SP2 obtained as part of the CUCBS facility. These calculations allow for the first time an evaluation of the performance of a wide variety of molecular mechanics force fields for peptides as compared to accurate quantum chemistry. Future work will involve examination of a wide range of different amino acids and peptide structural motifs, as well as extention of the approach to solution phase comparisons.